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The purpose of this paper is to investigate the process of fused filament fabrication (FFF) of a compliant gripper (CG) using thermoplastic polyurethane (TPU) material. The paper studies the applicability of different CG designs and the efficiency of some design parameters.

After reviewing a number of different papers, two designs were selected for a number of exploratory experiments. Using design of experiments (DOE) techniques to identify important design parameters. Finally, the efficiency of the parts was investigated.

The research finds that a simpler design sacrifices some effectiveness in exchange for a remarkable decrease in production cost. Decreasing infill percentage of previous designs and 3D printing them, out of TPU, experimenting with different parameters yields functional products. Moreover, the paper identified some key parameters for further optimization attempts of such prototypes.

The cost of conducting FFF experiments for TPU increases dramatically with product size, number of parameters studied and the number of experiments. Therefore, all three of these factors had to be kept at a minimum. Further confirmatory experiments encouraged.

This paper addresses an identified need to investigate applications of FFF and TPU in manufacturing functional efficient flexible mechanisms, grippers specifically. While most research focused on designing for increased performance, some research lacks discussion on design philosophy, as well as manufacturing issues. As the needs for flexible grippers vary from high-performance grippers to lower performance grippers created for specific functions/conditions, some effectiveness can be sacrificed to reduce cost, reduce complexity and improve applicability in different robotic assemblies and environments.

The assembly simulation in tolerance analysis is one of the most important steps for the tolerance design of mechanical products. However, most assembly simulation methods are based on the rigid body assumption, and those assembly simulation methods considering deformation have a poor efficiency. This paper aims to propose a novel efficient and precise tolerance analysis method based on stable contact to improve the efficiency and reliability of assembly deformation simulation.

The proposed method comprehensively considers the initial rigid assembly state, the assembly deformation and the stability examination of assembly simulation to improve the reliability of tolerance analysis results. The assembly deformation of mating surfaces was first calculated based on the boundary element method with optimal initial assembly state, then the stability of assembly simulation results was assessed by the density-based spatial clustering of applications with noise algorithm to improve the reliability of tolerance analysis. Finally, combining the small displacement torsor theory, the tolerance scheme was statistically analyzed based on sufficient samples.

A case study of a guide rail model demonstrated the efficiency and effectiveness of the proposed method.

The present study only considered the form error when generating the skin model shape, and the waviness and the roughness of the matching surface were not considered.

To the best of the authors’ knowledge, the proposed method is original in the assembly simulation considering stable contact, which can effectively ensure the reliability of the assembly simulation while taking into account the computational efficiency.

The research evaluated the feasibility of 3D dynamic fit utilizing female compression tops by comparatively analyzing the virtual and actual dynamic fit.

Six female participants were 3D body-scanned and photographed in compression tops in four types of athletic movements (pull-up, kettlebell swing, circle-crunch and sit-up). Fit measurements, waist cross-sectional areas, waist width, waist depth, numerical simulation of clothing pressure (kPa) and objective pressure measurements (kPa) were collected from 3D virtual animation, 3D fit scan data and actual photos with the four types of athletic motions. The data were comparatively investigated between virtual and actual dynamic fit.

The 3D-animated body was not reflected with human body deformation because only bone structure was changed while maintaining the constant forms of muscle and body surface in athletic movements. Due to this consistency of virtual dynamic fit, there were significant differences with the actual dynamic fit at the top length, shoulder width and waist cross-sectional areas. Also, the virtual dynamic pressure indicated significantly higher levels than the objective dynamic pressure while presenting no significant correlations at the front neckline, breast, lateral waist, upper back, back armhole and back waist.

This study is the first to verify multiple aspects of virtual dynamic fit using 3D digital technology. This study provided useful information about which aspects of the current virtual animation need to be improved to apply in the dynamic fit evaluation.

Soft robots are known for their excellent safe interaction ability and promising in surgical applications for their lower risks of damaging the surrounding organs when operating than their rigid counterparts. To explore the potential of soft robots in cardiac surgery, this paper aims to propose an adaptive iterative learning controller for tracking the irregular motion of the beating heart.

In continuous beating heart surgery, providing a relatively stable operating environment for the operator is crucial. It is highly necessary to use position-tracking technology to keep the target and the surgical manipulator as static as possible. To address the position tracking and control challenges associated with dynamic targets, with a focus on tracking the motion of the heart, control design work has been carried out. Considering the lag error introduced by the material properties of the soft surgical robotic arm and system delays, a controller design incorporating iterative learning control with parameter estimation was used for position control. The stability of the controller was analyzed and proven through the construction of a Lyapunov function, taking into account the unique characteristics of the soft robotic system.

The tracking performance of both the proportional-derivative (PD) position controller and the adaptive iterative learning controller are conducted on the simulated heart platform. The results of these two methods are compared and analyzed. The designed adaptive iterative learning control algorithm for position control at the end effector of the soft robotic system has demonstrated improved control precision and stability compared with traditional PD controllers. It exhibits effective compensation for periodic lag caused by system delays and material characteristics.

Tracking the beating heart, which undergoes quasi-periodic and complex motion with varying accelerations, poses a significant challenge even for rigid mechanical arms that can be precisely controlled and makes tracking targets located at the surface of the heart with the soft robot fraught with considerable difficulties. This paper originally proposes an adaptive interactive learning control algorithm to cope with the dynamic object tracking problem. The algorithm has theoretically proved its convergence and experimentally validated its performance at the cable-driven soft robot test bed.

The purpose of this study is to investigate the use of positive autoethnography for the consequences of conversion therapy. Life after conversion therapy is, for many, a life-changing episode, especially when combined with disfellowship. In recent years, positive autoethnography has grown substantially. The work of Tedeschi and Calhoun (2004), from the school of positive psychology, focuses on posttraumatic growth following a traumatic event or series of events.

Qualitative approach of positive autoethnography.

This innovative case study highlights personal struggles with grief, depression and suicidal ideation. In addition, the time elapsed has enabled a process to juggle with alternative ideas moving forward in salvaging a form of identity.

Treatment as usual psychological therapies (TAUPT) provide many unhelpful triggers due to the same jargon used in both conversion therapy and TAUPT. Away from TAUPT, this writing exercise may help as a stand-alone post-conversion recovery process.

The post-conversion recovery process will offer much-needed help with only a few face-to-face meetings to aid the posttraumatic growth writing exercise.

The suicide rates for sexual minority conversion therapy victims are eight times higher than those of other sexual minority groups and isolation levels. A single point of entry pathway for conversion therapy survivors is needed.

To the best of the author’s knowledge, the first of its kind to apply positive autoethnography using the model as a framework to understand the post-conversion therapy experience, looks for growth in five areas: relating to others, new possibilities, personal strength, spiritual change and appreciation of life.

This paper focuses on the application of a robotic technique for modeling a three-wheeled mobile robot (WMR), considering it as a multibody polyarticulated system. Then the dynamic behavior of the developed model is verified using a physical model obtained by Simscape Multibody.

Firstly, a geometric model is developed using the modified Denavit–Hartenberg method. Then the dynamic model is derived using the algorithm of Newton–Euler. The developed model is performed for a three-wheeled differentially driven robot, which incorporates the slippage of wheels by including the Kiencke tire model to take into account the interaction of wheels with the ground. For the physical model, the mobile robot is designed using Solidworks. Then it is exported to Matlab using Simscape Multibody. The control of the WMR for both models is realized using Matlab/Simulink and aims to ensure efficient tracking of the desired trajectory.

Simulation results show a good similarity between the two models and verify both longitudinal and lateral behaviors of the WMR. This demonstrates the effectiveness of the developed model using the robotic approach and proves that it is sufficiently precise for the design of control schemes.

The motivation to adopt this robotic approach compared to conventional methods is the fact that it makes it possible to obtain models with a reduced number of operations. Furthermore, it allows the facility of implementation by numerical or symbolical programming. This work serves as a reference link for extending this methodology to other types of mobile robots.

This paper aims to design an active shock absorber scheme for use in conjunction with a passive shock absorber to suppress the horizontal vibration of elevator cars in a smaller range and shorter time. The developed active shock absorber will also improve the safety and comfort of passengers driving in ultra-high-speed elevators.

A six-degree of freedom dynamic model is established according to the position and condition of the car. Then the active shock absorber and disturbance compensation-based adaptive control scheme are designed and simulated in MATLAB/Simulink. The results are analysed and compared with the traditional shock absorber.

The results show that, compared with traditional spring-based passive damping systems, the designed active shock absorber can reduce vibration displacement by 60%, peak acceleration by 50% and oscillation time by 2/3 and is more robust to different spring stiffness, damping coefficient and load.

The developed active shock absorber and its control algorithm can significantly reduce vibration amplitude and converged time. It can also adjust the damping strength according to the actual load of the elevator car, which is more suitable for high-speed elevators.

In complex environments, a spherical robot has great application value. When the pendulum spherical robot is stopped or disturbed, there will be a periodic oscillation. This situation will seriously affect the stability of the spherical robot. Therefore, this paper aims to propose a control method based on backstepping and disturbance observers for oscillation suppression.

This paper analyzes the mechanism of oscillation. The oscillation model of the spherical robot is constructed and the relationship between the oscillation and the internal structure of the sphere is analyzed. Based on the oscillation model, the authors design the oscillation suppression control of the spherical robot using the backstepping method. At the same time, a disturbance observer is added to suppress the disturbance.

It is found that the control system based on backstepping and disturbance observer is simple and efficient for nonlinear models. Compared with the PID controller commonly used in engineering, this control method has a better control effect.

The proposed method can provide a reliable and effective stability scheme for spherical robots. The problem of instability in real motion is solved.

In this paper, the oscillation model of a spherical robot is innovatively constructed. Second, a new backstepping control method combined with a disturbance observer for the spherical robot is proposed to suppress the oscillation.

This paper aims to examine the roles of quality managers at community colleges, their experiences balancing accountability and improvement and their insights into the future of quality assurance.

This phenomenological, qualitative study used semi-structured interviews with eight community college quality managers to investigate their roles, experiences and perspectives. A reflexive thematic approach was used to analyze the interview data.

Four themes were identified from participant responses: quality managers frame and enable program quality, quality managers drive program change, quality managers cultivate a culture of quality and quality managers seek system change. The findings illustrate the roles played by quality managers as they work to improve college education at program, institution and system-wide levels.

The decision of participants to accept the recruitment invitation might reflect particular attitudes, perspectives or experiences.

Quality assurance has emerged as a key mechanism for ensuring postsecondary programs are current, relevant and meeting the evolving needs of students and employers. This study advances the understanding of how quality assurance processes play out at the operational level and explores the experiences of quality managers as they navigate various quality tensions.

Quality managers play key roles in leading, evaluating and influencing quality assurance processes in postsecondary education yet they are underrepresented in the literature. The findings of this study shed new light on the aspirational and influential roles they play in advancing quality assurance.

In Denmark, there has been, over decades, an intensified political focus on how humanities research and doctoral education contribute to society. In this vein, the notion of impact has become a central part of the academic language, often associated with terms like use, effects and outputs, stemming from neoliberal ideologies. The purpose of this paper is to explore how humanities academics are living with the impact agenda, as both experienced researchers and as doctoral supervisors educating the next generation of researchers in this post-pandemic era. Specifically, the authors are interested in the supervisor-researcher relationship, that is, the relationship between how the supervisors navigate the impact agenda as researchers and then the way they tell their doctoral students to do likewise.

The authors have studied how the impact agenda is accommodated by humanities academics through a series of qualitative interviews with humanities researchers and humanities PhD supervisors, encompassing questions of how they are living with the expectation of impact and how it is embedded in their university and departmental context.

The study shows that there is no link between how the supervisors navigate the impact agenda in relation to their own research work and then the way they tell their doctoral students to approach it. Within the space of their own research, the supervisors engage in resistance practices towards the impact agenda in terms of minimal compliance, rejection or resignation, whereas in the space of supervision, the impact agenda is re-inscribed to embody other understandings. The supervisors want to protect their students from this agenda, especially in the knowledge that many of them are not going to stay in academia due to limited researcher career possibilities. Furthermore, the paper reveals a new understanding of the impact agenda as having a relational quality, and in two ways. One is through a positional struggle, the reshaping of power relations, between universities (or academics) and society (or the state and the market); the other is as a phenomenon very much lived among academics themselves, including between supervisors and their doctoral students within the institutional context.

This study opens up the impact agenda, showing what it means to be a humanities academic living with the effects of the impact agenda and trying to navigate this. The study is mapping and tracking out the many different meanings and variations of impact in all its volatility for academics concerned about it. In current, post-pandemic times, when manifold expectations are directed towards research and doctoral education, it is important to know more about how these expectations affect and are dealt with by those who are expected to commit to them.